Wireless signaling system.



G. MARGON I, WIRELESS SIGNALING SYSTEM.

' APPLICATION FILED NOV. 27, 1905. 924,168. Patented June 8,1909.

2 SHEETS-SHEET 1.

. Inventor:

I G. MAROONI.

-WIRELESS SIGNALING SYSTEM.

APPLICATION FILED NOV. 27, 1905.

Patented'June 8, 1909'.

2 SHEETS-SHEET 2.

, STATES PATENT oFFroE.

,GUGLIELMO MAECQNI, OF LONDON, ENGLAND, ASSIGNOE TO MARCONI WIRELESS TELE- GRAPH COMiP-ANY OF AMERICA,- OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

WIRELESS SIGNALING SYSTEM.

-No. basics.

- Specification of Letters Patent.

, Patented June 8, 1909.

' Application fi1edN:ovember27,1905. Serial No. 289,827.

To all whom it may concern:

- Be it known that I, GUcLIELMoMAnooNI,

a subject of the, King 'of Italy, residing in London, England, have invented certain 5 new and useful Im rovements in- Wireless Signaling Systems, 0 which the following is a specification. The object of this invention .is to provide improvedapjliaratus and s stems for com- 10 1 5 -t0 the emitted waves so enabling one station to signal to another without interfering with neighboring stations ,and also whereb are- "ceiving station can accurately and de 'tely ascertain from What sending station the signalsare coming. I i v j The object of. the invention is accom- 1pfiished by the apparatus diagrammatically ustrated in the accompanying drawings, in Y Figure lis a diagrammatic illustration of a transmitting station, and Fig. 2 is a similar "illustration of a receiving station, showing my improved apparatus in its simplest form; and F1gJ3 is an illustration of an arrangement of 'my improved antennae, which may be employed at either a transmitting station,-

- at a receivingstationor-both. Fig. 4 is a diagrammatic illustration ofa sending station and a receiving station, both employing ,my improved antenna, and Fig. 5 is a diagrammatic illustration of a sending station employing my improved antenna in con nection with a receiving station employing.

' the ordinary elevated conductor.

'lh'e' so-called Hertz waves or etheric disturbances produced by an electric discharge across a spark-gap in'the absence of modifying conductors, spread radially. outward in ever widening circles from thespark-gap or generating'center. When one side of the spark-gap is connected to a vertical radiating conductor, or antenna, and the other side of thesparkgap is connected to earth as in systems now incommon use the etheric disturb ances radiate from the vertical antenna "as a center. In the systems of wireless telegraphy now most commonly used these et eric disturbancesor Hertz waves fall upon the v'ertica'l'antenna at the receiving station.

and produce therein currents which are led to earth. Such waves, in the absence of modifying conductors, affect in equal degree .a receiving station located anywhere on a given circumference drawn around the generatingcenter.

, I ave discovered that if the vertical antenna at the transmitting station is discarded and if there is substituted therefor one or a llplurality of parallel or substantially ar-' a el conductors or antennae dispose in a horizontal or substantially horizontal straight line upon, or at a suitable distance above, the surface of the earth (ground 'or ,Water) and insulated-therefrom (as shown in Fig. 1), then this horizontal antenna servesto direct the Hertz waves or etheric disturbances in a definite direction, which direction is a prolongation of the straight line of the horizontal antenna itself. I have found that ifone end of such a horizontal antenna is connected to one side of a spark-gap, the

other side of which is earthed, then the Hertz waves or etheric disturbances are principally confined to a straight path which 1s. a prolongation of the line of the antenna from the end to which the spark-gap is connected, and that a receiver at a distance will be operated only if it is substantially within this straight path. Waves are also emitted from the other or free end of the antenna, but only to a small extent. The nearer to the ground that the antenna is disposed, the

more confined is the ath of the radiations,,-

but the antenna may e su ported above the round at a distance sma' compared to its orizontal length, in which case theradlations are som'ewhatmore powerful, but are not so restricted in direction, and the more the antenna is raised the more do the radiations tend to spread out.' By turning the antenna in a horizontal plane about the endto which the: spark-gap 1s connected,, signals may be emitted in any desired directlon; in other words, to signalto any desired station it is only necessary toturn the antenna so that 'its free end is pointing directly -away from that station.

When the horizontal antenna which I have' described is used atthe transmitting station, any receiving device and arrangement of receiving circuits may be used at the receiving station so long as it is located subst'antially within the path above described. Thus the vertical antenna now in ordinary usemay be employed at the receiving station. (As shown in Fig. '5). I have also found that a horizontal antenna of the character above described may advantageously be employed at a receiving station. In such case the end of the horizontal receiving antenna nearer to the transmitting station is earthed through a magnetic or other detector. With such an arrangement (as shown in Fig. 2) the receiver is operated principally by waves emitted from a generating center with respect to VHllOh the horizontal receiving antenna is radially disposed, or, in other words, the receiver is o erated only when the transmitting station is ocated substantially in a line constituting a prolongation of the horizontal antenna from its end to which the detector is connected, and at a much smaller distance by stations located in a continuation of the same straight line through the free end of the horizontal antenna. If, therefore, signals be best received with the antenna in a certain position, the operator Will know that the transmitting station is in the line of the antenna; in other words, that its free end is pointing directly away from the transmitting station. This receiving antenna may be used with great advantage to determine the direction of a transmitter, say for instance of a ship at sea, whether the transmitting antenna be of the kind above described or any ordinary antenna, such as a vertical antenna now in common use. By bisecting the angle between the limiting positions of the antenna in which signals can be detected, the direction of the transmitter can be ascertained with great accuracy.

I have described above the arrangement of my improved antennae at a transmitting station and at a receiving station, but it wil be understood that I may'utilize my improved antennae at both the transmitting station and the receiving station in the same signaling system. In such case, the two horizontal antennae should, of course, be arranged in substantial coincidence with the same strai ht line, as indicated in Fig. 4. In all cases ahove described, the horizontal antennae should be insulated from the earth, except for their respective connections through the spark-ga and detector; and it will e V understood t at when here I say insulated tor, as the case may be.

from the cart I mean so effectively insulated from the earth that the currents generated by or enerating the Hertz waves or etheric distur ances, shall be forced to pass to earth throughthe detector or Wave genera- Referring to Fig. 1 of the drawings, which shows a transmitting station, A is an antenna supported in substantial parallelism with the surface of the ground, or water. Gr.v

The end of the antenna A nearer the receiving station is connected, throughwire B, to

one side of the spark-gap O, the other side ofthe spark-gap being connected to ground. as

- improved antenna.

illustrated. The terminals of the spark-ga are illustrated as connected into the secon .ary circuit of a high tension transformer,

D, in a way which will be readily understood by those skilled in the art. The primary circuit of this transformer contains a generator,,H, of alternating current, and a key, K,

for closing the primary circuit.

In Fig. 2 is shown a, receiving station in which the antenna A is supported in substantial parallelism with the surface of the ground, in the manner described. The end of this antenna nearer the transmitting station is connected to one coil of a magnetic detector E, the other end of the'coil being grounded. This magnetic detector is of a character which is now well-known, and which is described in a paper entitled Note on a magnetic detector of electric waves which can be emplo ed as a receiver for space telegraphy, w ich was presented by me to the Royal Society and published in Volume 70, No. 463,.of the Proceedings of the Royal Society.

Fig. 3 is a top plan view of a plurality of horizontal conductors disposed substantially parallel with the surface of the earth, but in which all of them are disconnect-ed from the spark producer, if such conductor is used at the transmitting station, and from the receiving apparatus, if such conductor is used at the receiving station. When now it is desired to transmit a signal or message from the sending station to any particular receiving station, it will vbe obvious, from what I have described, that all that it is necessary to do is to connect to the transmitting apparatus that particular horizontal wire conductor which 18 in a substantially coincident line with the receiving station to which it is desired to transmit a message. Similarly, if it is desired to receive a message from any one of a number of transmitting stations located in different localities, all that it is necessary to do is to connect to the receiving station that articular horizontal receivin antenna whic' is in a coincident line to suc sending station.

Fig. 4 illustrates a receiving station and a transmitting station, ,both em loying my At the sen 'ng station is the t rough a wire B to the secondary coil of the oscillation transformer T. The rimary coil of this transformer is connected in' a closed resonant circuit with the spark-gap C and the secondary coil of the transformer D and capgcity, in the inanner which is now well own. The primary coil of the transformer D is oonnecte in circuit with the enerator H and the circuit-closing key K. t the rehorizontal antenna connected ceiving station A is the horizontalreceiving the .5 magnetic detector at the receiving station,

I wish it to be clearly understood that the invention is in no way limited to any particular form or arrangement of spark gap circuit con- 7 nections, or to any particular form of detector and circuit connections,'but it may be employed with any arrangement of transmittingapparatus and receiving apparatus, as a substitute for ,the vertical antennae and grounded connections which are now in use.

What I claim as my invention, and desire to secure by Letters Patent is:

1. In a wireless signaling system, a terminal station, an antennasituated at said station and disposed substantially parallel with the surface of theearth, the position of the antenna being substantially coincident with the line of direction in which it is desired to transmit or recelve signals, said antenna havmg a connection w th earth at its end nearer f; the distant station, and suitable signaling apparatus in said connection. r v

2, In a wireless signaling system, a transmitting station, an antenna situated at said station and disposed substantially parallel with the surface of the earth, the horizontal position of the antenna being substantially coincident with the line ofdirection to a receiving station,'a nd means, havin its terminals connected with earth and wit an end of said antenna nearer the distant statlon', for

im res'sing upon said antenna electrical os oil ations of-hi h frequency.

3. In a wireess signaling system employing electrical oscillations of high frequency, a receiving antenna comprisin a conductor "disposed substantially parallel with the surface ofthe earth and connected with earth at one end and having its free end extended radiallybut in the opposite direction withrespect to the generatingcenterand suitable receiving apparatus interposed in said earth connection. I I

4. In a wireless signaling system,'a pluralated at said station and disposed substan-' tially parallel with the surface of the earth but radiating from a common center, a set of wireless telegraph apparatus at said station, and means for independently connecting any one of the antennae to said apparatus.

5. In a wireless signaling system employing electrical oscillations of high frequency, a plurality of receiving antennae situated at ity of electrically independent antennae, situ I 0 one station and comprising electrically indeendent conductors disposed substantially parallel with the surface of the earth, each of said conductors extending radiallyin the opposite direction, in relation to its respective generating center, and means for detecting electric signals adapted to be independently connected with any one of said conductors.

In testimonywhereof, I have signed my name to this specification in. the presence of two subscribing witnesses.

GUGLIELMQ 'MARconL Witnesses: I

JAMES J. Cosenovn, WILLIAM H. DAVIS. 

